Well, of course it is – and a very useful tool for **B&W processing as well (we might as well get past the perceived ‘immiscibility’ of HDR and B&W processing right at the beginning…)
HDR is a name which brings a new sheen to a process ages old – dodging and burning. Opening up the shadows to find detail, the same in closing down the highlights a tad. Judicious dodging and burning – but done all at once in a software package – has been dubbed HDR. “Bad” HDR is what early adopters called excellent – that sooty, grimy, OTT look. But HDR has matured to the point that we really do see that excellence in HDR involves judicious application of presets, and then masking to brush-in or brush-out the effect. HDR now that it has gotten away from its roots, tends to mean that balance between brights and darks – and mid-tones – which the ‘averaging-machine’ aka the camera – could not do on its own. There is still a place for that sooty grimy gritty look – and in the right hands it looks excellent. Luminance Masking is making great inroads against that colossus of HDR, Photomatix, and its counterpart in Google/Nik’s HDRfxPro. Until cameras can get that balance right all by themselves, the D+B that is HDR is always going to be a very useful – and some say irreplaceable – feature of photographic post-processing.
** As a tool to achieving tonal separation – a very necessary quality of black and white processing – a single raw or jpeg into an HDR software package can greatly aid the pursuit of tonal separation (only control both the halos and the grittiness/noise), and save hours and hours of the brush technique that is manual dodging and burning. Luminance Masking is a great way to get very fine control over tonal separation. Jimmy McIntyre has a great tutorial included in his 1.7Gb Megapack (and all for free!) I recommend.